Week 17 - Applications and Implications, Project Development
Assignment
Propose a final project masterpiece that integrates the range of units covered.
Your project should incorporate:
2D and 3D design
Additive and subtractive fabrication processes
Electronics design and production
Embedded microcontroller interfacing and programming
System integration and packaging.
Where possible, you should make rather than buy the parts of your project.
Projects can be separate or joint, but need to show individual mastery of the skills, and be independently operable.
See Final Project Requirements for a complete list of requirements you must fulfil.
Project: Bionic Hand
What will it do?
My project is a bionic hand that mimics human finger movements using servos. It will be controlled by signals derived from electromyography (EMG) electrodes placed on the user’s arm. The setup consists of two microcontrollers: one reads the muscle signals from the arm and sends data to the second microcontroller, which activates corresponding finger movements on the bionic hand. The system is powered by a battery and aims to support users with upper limb disabilities in basic grasping and hand movement tasks.
Who has done what beforehand?
Various open-source and commercial bionic hand projects exist, including Motorized Bionic Hand and InMoov, which use servo motors and EMG signals to replicate hand movements. These projects often use a single board for both signal acquisition and motor control. My project explores separating signal reading and actuation into two microcontrollers communicating wirelessly.
What will you design?
Enclosure
- Arm-mounted sensor case
- Palm and finger structure of the hand
Electronics
- Custom PCBs for signal acquisition and servo contro
- Power distribution system for battery and voltage regulation
Mechanical
- Articulated 3D printed fingers
- Servo mounts and tendon routing system
What materials and components will be used?
| Item & Description | Quantity | Price | Source | Notes |
|---|---|---|---|---|
| ESP32 wroom microcontroller | 2 | Frw 8,000 | https://nyerekatech.com/shop/esp-32s-esp-wroom-32/ | One for EMG sensors, one for servo control on the fingers |
| Servo motors | 5 | Frw 3,800 | https://nyerekatech.com/shop/sg90-9g-mini-micro-servo-motor/ | One for each finger |
| 3D Printing Filament (PLA) | 1 | Frw 50,000 | https://nyerekatech.com/shop/light-blue-pla-filament-1-75mm-1kg-roll-for-3d-printer/ | For printing the hand and enclosure |
| Lepo Battery | 1 | Frw 10,000 | https://nyerekatech.com/shop/3-7v-dtp-654065-lipo-battery-2000mah-rechargeable-battery/ | Powers the EMG sensor in the arm case |
| 5V 2A Power Supply | 1 | Frw 5,000 | https://nyerekatech.com/shop/5v-3a-dc-power-supply-220v-ac/ | Powers the servo motors with a 5v |
| Plastic Cord (Fishing Line) | 2 | Frw 2,000 | Connecting finger tips to servo motors and tendon |
What parts and systems will be made?
- 3D printed bionic hand, including palm and articulated fingers
- Sensor enclosure for arm-mounted EMG setup
- Custom PCB for EMG signal processing
- Control board (PCB) for servo control
- Power management system to control and supply both microcontrollers and servos with power
What processes will be used?
- CAD for mechanical design (SolidWorks)
- 3D printing
- PCB design and milling
- Soldering and circuit assembly
- Embedded programming (Arduino IDE)
- Wireless communication between microcontrollers
What questions need to be answered?
- Can the microcontrollers reliably communicate fast enough for responsive finger motion?
- Will a single set EMG sensors provide enough distinct signals for multiple finger control?
- How to minimize power consumption while maintaining functionality?
What problems need to be solved?
- Noise filtering and amplification for EMG signal
- Smooth and proportional control of servo motors
- Mechanical durability of finger joints
- Efficient use of battery power for extended usage
How will it be evaluated?
The bionic hand should:
- Respond in real time to EMG signals
- Accurately move individual or grouped fingers
- Run for a reasonable duration on battery power
What tasks still need to be completed?
- Finalize CAD design for arm enclosure
- Integrate EMG sensor with microcontroller
- Design and build the power management system
- Calibrate and fine-tune servo response to EMG input
- Conduct user testing and evaluations
What has worked?
- 3D printed finger prototypes with tendon actuation
- Basic communication between ESP32 wroom boards
What has not worked yet?
- Full integration of EMG with servo control
- Stabilization of signal for real-time movement
- Complete enclosure design for arm module
What have you learned?
- Practical use of CAD and digital fabrication to match human anatomy
- Designing reliable circuits using custom PCBs
- Translating physiological signals into mechanical action using microcontrollers
This content was paraphrased and refined using Grammarly AI.